Currently, a storage system having a storage device and a control device for controlling an access to the storage device has been widely distributed. In such a storage system, a fault tolerance may be improved by making a communication route from the control device to the storage device to be redundant. As such a system, for example, a storage system having a communication route passing through a first relay device and a communication route passing through a second relay device has been proposed.
In the storage system, the control device may be made redundant. In such a system, for example, a storage system is proposed in which when one control device detects that an abnormality has occurred in a first route to a disk, the one control device communicates with the other control device to allow the one control device to access the disk by using a second route to the disk based on a result of the communication.
Related technologies are disclosed in, for example, International Publication Pamphlet No. WO 2012/032607 and Japanese Laid-Open Patent Publication No. 2009-157859.